/*
 * Copyright (C) 2020-present, kinbug All rights reserved.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.gitee.kinbug.sniper.indicator;

import java.math.BigDecimal;
import java.util.List;

/**
 * -标准差
 * @ClassName: StandardDeviationIndicator
 * @author kinbug
 * @date 2020-11-20
 */
public class StandardDeviationIndicator {

	/**
	 * 标准差MD
	 * @param list 求标准差源数据 
	 * @param EMAValue 移动平均值EMA
	 */
	public static BigDecimal getValue(List<BigDecimal> list, BigDecimal EmaValue) {
		BigDecimal sum = BigDecimal.ZERO;
		for (int i =0; i < list.size() ; i++) {
			BigDecimal diffValue = list.get(i).subtract(EmaValue);
			sum = sum.add((diffValue.multiply(diffValue)));
		}
		return  new BigDecimal(Math.sqrt(sum.divide(new BigDecimal(list.size())).doubleValue()));
	}
}
